Hydrodynamic fluid coupling



AugG 23g, 193 F. KUGEL.

HYDRODYNAMIC FLUID COUPLING Filed Aug. 10 1936 2 Sheets-Sheet l Aug. 23p1933.. F, KUGEL 2,127,738

HYDRODYNAMIC FLUID COUPLING Filed. Aug. 1o, 1936 2 sheets-sheet 2Patented Aug. 23, ,1938

Application August 10, 1938, Serial No. 95.301

In Germany August 14, 1935 l '14 claim (01; iso- 54) The inventionrelates to hydraulic power transmitting devices, such as ,hydrauliccouplings or Atorque converters, and iii-particular to the provision, insuch devicesgwofs. rotating reservoir chamber connected by separatepassages to the working chamber so as. to take up the workingfiuidtemporarily notl required, and thereby to enect a quick emptyingand lling of the fluid circuit.

Hitherto, in such devices. the discharge of the working fluid to thereservoir chamber has frequently been effected by scoop tubes whichstarted to work as soon as a sumciently large difference in speedexisted between the fluid and the scoops. l

In such prior devices the fluid returned to the reservoir chamber fromthe working chamber through the same canals by which it entered, as

soon as the slip decreased in response to a change in the operatingconditions. By this use of a common intake and discharge passage, eitherthe filling or the emptying conditions were interfered with andunfavorably inuenced.

One object ofthe present invention is to provide a hydraulic powertransmitting device wherein two separate connections between thereservoir chamber and the working chamber allow the working fluid toenter and leave the working chamber by separate paths, thus providingthe most favorable arrangement for filling and emptying the workingchamber. l v

, Another object is to provide such a device wherein the reservoirchamberv is arranged in the primary or driving part of the devicebyreason of the fact that the latter rotates always at maximum speed sothat theV working fluid storedy there stands under high pressure, due tocentrifugal force.` If the speed of the prime mover operating theprimary or drivingv part of the hydraulic coupling or torque convertercan be varied, centrifugal force may be utilized to effect 'the entranceof theV working fluid from the rotating reservoir chamber into theworking chamber through passages in the primary wheel, these beingpreferably adjustable. The centrifugal force may be varied by changingthe speed and thus the slip between the wheels. If the 4speed of theprime mover is not variable, a valve is arranged to control the supplyof fluid to and from the working chamber and rotating chamber,respectively. This valve, operated automatically or manually, controls'the supply of working iluid from the reservoir chamber to the workingchamber.

Another object is to provide such a device with scoops at thecircumference of the secondary part,

these scoops being arranged toleifect a complete emptying of the workingchamber. In ,order to obtain the large slip between primary andsecondary parts necessary for the working of the scoops, the speed ofthe primary wheel is either 5 decreased or the discharge valve of thereservoir chamber 'is connected to a ring valve which may throttle oreven interrupt the flowv of fluid to the working chamber.' .v

In the drawings:

Figure 1 is a vertical longitudinal sectionv through a iluid coupling'with a control valve in its closed position.

Figure 2 is a similar section through a uid coupling with the controlvalve in its open posil5 tion.

Figure 3 is a similar section through a fluid coupling having anautomatic regulating device for the control valve. f A

Figure 4 is a cross section along the line l-l inV 20 Figure 1, showingthe scoop tube construction.

Referring tothe drawings in detaiLin Figure 1 the primary wheel a isconnected with a variable speed engine by the driving shaft al. Thesecondary wheel bis mounted on the driven shaftbl.' Awall 26 a2connected-with the primary wheel a, togetherwith the back of the latter,forms the rotating chamber u, while coupling casing aii extends over thesecondary part-or turbine wheel b and forms a bearing for shaft b1 andis sealed against the 30 v shaft b1 by the'stuillng box f. Primarywheelv a is provided with passages p the openings of which arepreferably adjustable. These passages p form a connection between thechamber u and the core space r. In the secondary part h, scoops m and 35canals n are provided to return the working fluid from the transmissioncircuit to the chamber u along overiiow edget.'

When starting the coupling, the secondary part b of the coupling is at'rest. As the speed ofthe 40 primary part a. increases, the fluid in thechamber u is urged from the chamber u, through the passages p bycentrifugalV force, thus filling the fluid circuit, i. e. engaging thecoupling. With decreasing speed of the engine, and thus of the A4&5primary part a, the scoops m gradually come into operation, due to theincreased slip, and empty the fluid circuit` to the chamber u,

In Figures 1 and 2 the blade wheel, driven by a constant speed engine,is marked a.. This `wheel 50 is connected with the engine shaft al bymeans of a shell a, which is integral with the engine shaft a1. Bladewheel b is fastened on the shaft b1 of the machine, to be driven andinclosed by the coupling casing a3 connected to the primary blade 55cated, the valve s1 closes the blade canals ofy wheel a. The couplingcasing a.l forms a bearing for the output shaft b1 and is sealedthereagainst by means of the stuffing box f. The back of the primaryblade wheel a and the shell a2 connected thereto, inclose the hollowspace u serving as a reservoir chamber for the working fluid which istemporarily not required by the coupling. A number of passages p leadfrom this chamber to the core space r of the coupling. These passages pcan be closed by the valve body s, to which the ring valve s1 isconnected. In the position indithe primary wheel and at the same timethe annular portion sa also closes the passages p leading to the corespace r. 'I'he valve body s can be adjustably moved from the outside,adjusting sleeve i in an axial direction through the operatingconnection formed by the pin j and the slot k. By moving the valve bodys towards the driving shaft al, the circuit is thereby opened forworking fluid through the blade canals of the primary wheel a from thereservoir chamber u by way of the core space r and passages p. Secondaryblade wheel b is fitted with scoops m connected by canals n to the partof chamber u near the axis.

When starting with the valve s1 closed (Figure l) the secondary part orrotor b is at rest. With increasing speed of the primary part or rotora, however, any fluid that might have remained between the blade wheelswill be thrown out by centrifugal force, caught by the scoops 1n and ledthrough the canals n to the space q near thev axis, whence it then flowsback to the chamber u. Since a return of the fluid accumulated in thechamber u into the working circuit is made impossible by the closedcondition of the valve s1. an almost complete discharge of the workingfluid from the coupling spaces a, b, q and r to the chamber `u issecured. This means that the coupling cannot transmit any torque whenstarted with the valve 81 in this condition.

The working fluid accumulated in the chamber u is now influenced bytherotating walls and subjected to centrifugal pressure. As soon as thevalve body s is moved to the left by meanslof displaceable sleeve i(Figure 2). the consequent shifting of the ring valve sl uncovers thepassages p so that the fluid passes through the passages 'p into theworking space of the coupling at high velocity. The coupling therebyacquires the capacity to transmit torque, i. e. the coupling is engaged.Secondary runner b then starts to rotate, whereupon the fluid which isstill discharged by scoops m to the rotating axis does not reach thechamber u any more, but is immediately returned to the coupling spacesa, b and r by centrlfugal force. The scooping efi'ect of the scoops mdecreases with the increasing speed of the secondary wheel b and finallyceases completely, due to the centrifugal force counteracting thevpassage of the iluid through the canals n. @The coupling spaces a. b andr thusremain completely filled, 'whereby the full transmitting capacityof the coupling is obtained.

.When stopping the coupling, the valve body-s is moved to the right(Figure 1) whereupon the ring valve s1 closes the openings to the bladecanals ofthe wheels a and b, and simultaneously closes the passages p.This interruption of the fluid circuit immediately causes a considerablereduction in the transmission capacity of the coupling so that the speedof the secondary wheel b decreases considerably, due to the load on themachine being driven. This speed reduction I,

causes the scoops mito become-operative again to return the fluid to thechamber u so that finally a complete emptying and disengagement of thecoupling is again obtained, and the driven machine comes to rest.

In order to assist the flow of the fluid from the secondary wheel b tothe chamber u, it is preferred to provide the secondary wheel b with anoverflow edge t projecting into the chamber u. It is further preferredto construct the valve body s in such a manner that it will also formone of the lateral limiting walls of the chamber u. Accordingly, whenthe valve body s is moved, for the purpose' of filling and thus engagingthe coupling, this wall will have a displacing effect on the uid in thechamber u, whereby the filling of the coupling is accelerated.

Thus it will be seen that in the operation of the coupling shown inFigures 1 and 2 the fluid contained in the space u is urged outwardly byreasonof the centrifugal force created by the rotation of the coupling.'I'his fluid is forced ythrough the bores p in the coupling rotor a. by

reason of this centrifugal force, when the valve member s and itsannular portion s3 are shifted to the left, as shown in Figure 2. Thusthe ring slide valve s1. and the annular portion sa cooperate to producethe desired result. 'Ihe ring slide valve s1, by altering thecirculation within the coupling rotors a and b, increases the slip inthefrotor a so y that the scoop tube comes into operation, whereupon thefluid within the rotors and b is conducted through the scoop tubes m andthe space q into the chamber u. To prevent the escape of the fluid atthe same time through the bores p, the annular portion sa comes intoaction, and closes the inlets to the bores p. When it is desired to fillthe coupling again, the slip is once more reduced by moving the slidevalve s1 and annular ,portion s by shifting \the shift member i so thatthe working fluid canlflow freely through the bores p, from the chamberu, to the rotors a. and b of the coupling.

In the modined construction of Figure 3 there is shown means to providefor an automatic engaging and disengaging ot the coupling in response tothe' input and output speeds or to the slip. This is realized byutilizing a centrifugal mechanism c, which becomes operative te displacethe valve body s as soon as a certain speed is exceeded. Thiscentrifugal mechanism c consists of a ily weight c1, on an arm c.pivotally mounted on the pivot member c. Likewise mounted upon the pivotmember ca is an arm c4, pivotally connected at' its opposite end to alink c. The link c* is pivotally attached to a lug s mounted upon thevalve body s.

In the operation of the apparatus shown in Figure 3, the rotation of thecasing aI creates centrifugal force which causes the ily weight c1 tomove outward, swinging the arm c4 to move the link ci to the left.lIfhis action shifts the valve body s to the left, overcoming the thrustof the coil spring h1 and causes' the ring valve s1 to Open thepassages.

It will be understood that I desire to comprehend within this inventionsuch modifications as come within the 'scope of the claims and theinvention.

. I claim: 4 A

1. In a hydraulic power transmitting device, aworking chamber, a drivingrotor and a driven rotor therein, and inclosing casing for said deviceadditionally forming the outer wall of a rol tatable reservoir connectedto one of said rotors for' varying the flow of fluid through both ingsaid reservoir and said working chamber, a-

valve member arranged adjacent said fluid pas# sage and movablerelatively thereto for varying the flow of iluid therethrough, and meansresponsive to the rotation of one 'of said rotors for automaticallyvarying the setting of said valve member.

3. In a hydraulic power transmitting device, a working chamber, adriving rotor and a driven rotor therein, a rotatable reservoirassociated in one oi said rotors, a uid passage interconnectber toward iing said reservoir and said working chamber, and a valvemember having.portions movable relatively to said uid passage and also relatively tothe iluid circuit within said working chamber for varying the now ofiiuid through both said iiuid passage and said working chamber iluidcircuit. 4. In a hydraulic power transmitting device, a Working chamber,a driving rotor and a driven rotor therein, a rotatable reservoirassociated in one of said rotors,a huid passage interconnecting saidreservoir and said working chamber, a

-valve member arranged adjacent said iluid passage and movable`relatively thereto for varying the flow of iluid therethrough, meansresponsive to the rotation oi one oi' said rotors for automaticallyvarying the setting of said valve member, and yielding means urging saidvalve memclosed position.

5. In a hydraulic power transmitting device, a working chamber, adriving rotor and a driven rotor therein, a rotatable reservoirassociated in one of said rotors, a fluid passage interconnecting saidreservoir and said working chamber, a. valve member having portionsmovable relatively to said iluid passage and also relatively to theiluid circuit within said working chamber for varying the iiowot fluidthrough both said fluid passage and said working chamber fluid circuit,

and yielding means urging said valve member toward its closed position.

6. In a hydraulic power transmitting device, a working chamber, adriving rotor and a driven rotor therein, an inclosing casing Iorsaiddevice additionally forming the outer wall o! a rotatable reservoirconnected to one oi said rotors and 'extending' substantially to theperiphery thereof, a`relatively short fluid intake passage extendingfrom said reservoir at a location near vthe periphery of one of saidrotors to' said working chamber, a'separate discharge passage extendingirom said working chamber to said reservoir, and a peripherally disposedvalve member arranged adjacent said intake passage `and movablerelatively thereto for varying the ilow of iiuid therethrough.

'7. In a hydraulic power transmitting device, a working chamber, adriving rotor and a driven rotor forming a working circuit therein, ahuid reservoir, a iiuid passage interconnecting said iiuid reservoir andsaid working chamber, and a valve member having portions movablerelatively' to both said iluid passage and working circuit l'a workingchamber, a

` rotor forming a working circuit therein, reservoir, a iluid passageinterconnecting said and peripherally said iluid passage and saidworking circuit.

8. In a hydraulic power transmitting device, driving. rotor and a drivenrotor forming' a workingcircuit therein, a iiuid reservoir, a fluidpassage interconnecting said `iiuid reservoir and said working chamber,and a valve member having portions movable rela'- tively to both saidiiuid passage and working circuit for varying the ilowv oi `iiuiclthrough both the said iiuid passage and said working circuit,

across said fluid passage and said working circuit, whereby to valve theduid flow therethrough by a single motion of said valve.

9. Ina hydraulic power transmitting device, a working chamber, a drivingrotor and a driven iiuid reservoir and said working chamber, a valvemember' having portions movable relatively to both said iluid passageand working circuit for varying the flow oi' fluid through both the saiduid passage and said working circuit, and means responsive to therotation oi.' one of said rotors for automatically varying the settingof said valve member.

10. In a hydraulic power transmitting device, a working chamber, adriving rotor and a driven rotor forming a working circuit therein, ailuid reservoir, `a iluidv passage interconnecting said fluid reservoirand said working chamber, a valve member having portions movablerelatively to both s aid uid passage and working circuit i'or varyingthe ilow of uid through both the said iiuid passage and said workingcircuit, and yielding means urging said valve member toward its closedposition.

11. In a hydraulic power transmitting device,`

` a working chamber, a driving rotor and a driven rotor therein, aninclosing casing for said device additionally forming the outer wall ofa rotatable reservoir connectedv to one of said rotors and extendingsubstantially to the periphery thereof, a iiuid intake passage extendingfrom the pe-f riphery of said reservoir to said working chamber, aseparate iiuid discharge passage interconsaid valve portions beingmovable simultaneously ilk a iiuid,

necting said reservoir and said working chamber,

and peripherally disposed valve means for con trolling the flow of iluidthrough one'of said passages.

l2. In a hydraulic power transmitting device, a working chamber, a.driving rotor and a driven rotor therein, an inclosing casingfor said.device additionally forming' the outer Wall of a rotatable reservoirconnected to one of said rotors'and extending substantially to theperiphery thereof, y

Va iiuid intake passage extending from the periphery of said reservoirto said working chamber, a separate iiuid discharge passageinterconnecting said reservoir and said working chamber, disposed valvemeans having a valve member disposed near the periphery-of one of saidrotors for controlling the ilow of iiuid through said intake passage.

13.` In a hydraulic power transmitting device, a working chamber, adriving rotor and a driven rotor therein, a' rotatable reservoirassociated '.with one of said rotors, a fluid intake passage and a fluiddischarge passage interconnecting said reservoir and said workingchamber, valve means for controlling the ilow of fluid through one ofsaid passages, and means responsive to the rotation of one oi'saidrotors for automatically varying the setting of said' valve means.

14. In a hydraulic power transmitting device. a working chamber, adriving rotor and a driven rotor therein, an inclosing casing for saiddevice additionally forming the outer wail o! a rotatable reservoirconnected to one oi said rotors and extending substantially to theperiphery thereof, a relatively short iiuid intake passage extendingfrom the periphery of said reservoir to said working chamber, a separatefluid discharge passage interconnecting said reservoir and said workingchamber, valve means having a valve member disposed near the peripheryof one of said rotors adjacent said working chamber for controlling thenow of uid through said intake passage, and a scoop on said dischargepassage within said working chamber arranged to assist the emptying. 5

driven rotors.

FRITZ KUGEL.

